package collection;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

/** List集合*/
public class ListDemo {
    public static void main(String[] args) {

        List<String> list=new ArrayList<>();
        list.add("1");
        list.add("2");
        list.add("3");
        list.add("4");
        list.add("5");
        list.add("6");
        list.add("7");

        System.out.println(list);


         String e=list.get(3);//获取指定下标元素
        System.out.println(e);
        for (int i = 0; i <list.size() ; i++) {
            System.out.println(list.get(i));
        }
        Iterator<String> it=list.iterator();
        while (it.hasNext()){
            System.out.println(it.next());
        }for (String l:list){
            System.out.println(l);
        }
        String old=list.set(2,"5");
        System.out.println(list);
        System.out.println(old);

        String s=list.remove(3);
        System.out.println(list);
        System.out.println(s);


        list.add(5,"22");
        System.out.println(list);
    }
}
